Semiconductor device and method of manufacturing the same

• US 6,720,577 B2
• Filed: 08/31/2001
• Issued: 04/13/2004
• Est. Priority Date: 09/06/2000
• Status: Expired due to Term

• Current Assignee: Semiconductor Energy Laboratory Co., Ltd.
• Original Assignee: Semiconductor Energy Laboratory Co., Ltd.
• Inventors: Isobe, Atsuo, Takayama, Toru, Arao, Tatsuya
• Primary Examiner(s): Hu, Shouxiang
• Application Number:
  US09/943,965
• Publication Number:
  US 20020027247A1
• Time in Patent Office: 956 Days
• Field of Search: 257/57, 257/59, 257/61, 257/66, 257/72, 257/532, 257/534, 438/48, 438/128, 438/149, 438/151, 438/157, 438/283, 438/255, 438/398, 438/665, 438/964, 438/957, 349/39, 349/42, 349/43, 349/47, 349/139
• US Class Current: 257/59
• CPC Class Codes: G02F 1/133305 Flexible substrates, e.g. plastics, organic film
• CPC Class Codes: G02F 1/1362 Active matrix addressed cells G02F1/134336, G02F1/134363 take precedence
• CPC Class Codes: G02F 1/136213 Storage capacitors associated with the pixel electrode
• CPC Class Codes: G02F 1/136227 Through-hole connection of the pixel electrode to the active element through an insulation layer
• CPC Class Codes: G02F 1/136295 Materials; Compositions; Manufacture processes
• CPC Class Codes: H01L 27/124 with a particular composition, shape or layout of the wiring layers specially adapted to the circuit arrangement, e.g. scanning lines in LCD pixel circuits wiring structures per se H01L23/52
• CPC Class Codes: H01L 27/1255 integrated with passive devices, e.g. auxiliary capacitors
• CPC Class Codes: H01L 29/66742 Thin film unipolar transistors
• CPC Class Codes: H01L 29/78603 characterised by the insulating substrate or support H01L29/78657 takes precedence
• CPC Class Codes: H10K 59/12 Active-matrix OLED [AMOLED] displays

Abstract

In a semiconductor device having a substrate which has a metal surface, an insulating film which is formed on the substrate having the metal surface, and a pixel unit which is formed on the insulating film; the pixel unit includes a TFT, and wiring lines connected with the TFT, and a storage capacitor is constituted by the substrate (11) having the metal surface, the insulating film (12), and the wiring line (21). As the insulating film is thinner, and as the area of a region where the insulating film and the wiring line lie in contact is larger, the storage capacitor is endowed with a larger capacity.

Claims

1. A semiconductor device comprising:

a substrate having a metal surface;

a base insulating film formed in contact with said substrate having said metal surface;

a pixel unit formed over said base insulating film, said pixel unit comprising a thin film transistor having at least a semiconductor layer and a gate electrode with a gate insulating film interposed therebetween;

a first insulating film covering said gate electrode and said semiconductor layer;

a portion of said first insulating film is removed so as to expose a portion of said base insulating film;

a metal wiring formed on said portion of said base insulating film and electrically connected to said semiconductor layer; and

a storage capacitor comprising a portion of said substrate having said metal surface, said portion of said base insulating film, and said metal wiring.

2. A semiconductor device according to claim 1, wherein said metal surface of said substrate has a maximum roughness of 1 μ

m or less.

3. A semiconductor device according to claim 1, wherein a radius of curvature of a convex part existing in said metal surface of said substrate is 1 μ

m or more.

4. A semiconductor device according to claim 1, wherein said substrate comprises a stainless steel substrate.

5. A semiconductor device according to claim 1, wherein said semiconductor device is a liquid crystal display device.

6. A semiconductor device according to claim 1, wherein said semiconductor device is at least one selected from the group consisting of a portable telephone, a video camera, a digital camera, a goggle type display, a personal computer, a DVD player, an electronic book, a mobile computer, and a portable information terminal.

7. A semiconductor device comprising:

a substrate having a metal surface;

a base insulating film formed in contact with said substrate having said metal surface;

a pixel unit formed over said base insulating film, said pixel unit comprising a thin film transistor having at least a semiconductor layer and a gate electrode with a gate insulating film interposed therebetween;

a first insulating film covering said gate electrode and said semiconductor layer;

a portion of said first insulating film is removed so as to expose a portion of said base insulating film;

a metal wiring formed on said portion of said base insulating film and electrically connected to said semiconductor layer;

a pixel electrode electrically connected to said metal wiring; and

a storage capacitor comprising a portion of said substrate having said metal surface, said portion of said base insulating film, and said metal wiring.

8. A semiconductor device according to claim 7, wherein said metal surface of said substrate has a maximum roughness of 1 μ

m or less.

9. A semiconductor device according to claim 7, wherein a radius of curvature of a convex part existing in said metal surface of said substrate is 1 μ

m or more.

10. A semiconductor device according to claim 7, wherein said substrate comprises a stainless steel substrate.

11. A semiconductor device according to claim 7, wherein said semiconductor device is a liquid crystal display device.

12. A semiconductor device according to claim 7, wherein said semiconductor device is at least one selected from the group consisting of a portable telephone, a video camera, a digital camera, a goggle type display, a personal computer, a DVD player, an electronic book, a mobile computer, and a portable information terminal.

13. A semiconductor device comprising:

a substrate having a metal surface;

a base insulating film formed in contact with said substrate having said metal surface;

a pixel unit formed over said first insulating film, said pixel unit comprising a thin film transistor having at least a semiconductor layer and a gate electrode with a gate insulating film interposed therebetween;

a first insulating film covering said gate electrode and said semiconductor layer;

a portion of said first insulating film is removed so as to expose a portion of said base insulating film;

a metal wiring formed on said portion of said base insulating film and electrically connected to said semiconductor layer;

a second insulating film formed on said metal wiring;

a pixel electrode formed on said second insulating film and electrically connected to said metal wiring; and

a storage capacitor comprising a portion of said substrate having said metal surface, said portion of said base insulating film, and said metal wiring.

14. A semiconductor device according to claim 13, wherein said metal surface of said substrate has a maximum roughness of 1 μ

m or less.

15. A semiconductor device according to claim 13, wherein a radius of curvature of a convex part existing in said metal surface of said substrate is 1 μ

m or more.

16. A semiconductor device according to claim 13, wherein said substrate comprises a stainless steel substrate.

17. A semiconductor device according to claim 13, wherein said semiconductor device is a liquid crystal display device.

18. A semiconductor device according to claim 13, wherein said semiconductor device is at least one selected from the group consisting of a portable telephone, a video camera, a digital camera, a goggle type display, a personal computer, a DVD player, an electronic book, a mobile computer, and a portable information terminal.

19. A semiconductor device according to claim 13, wherein said second insulating film comprises one selected from the group consisting of a polyimide film, an acrylic resin, a polyamide film, and a BCB (benzocyclobutene) film.

21. A semiconductor device according to claim 19, wherein a surface of said metal substrate has a maximum roughness of 1 μ

m or less.

22. A semiconductor device according to claim 19, wherein a radius of curvature of a convex part existing in a metal surface of said metal substrate is 1 μ

m or more.

23. A semiconductor device according to claim 19, wherein said metal substrate comprises a stainless steel substrate.

24. A semiconductor device according to claim 19, wherein said semiconductor device is a liquid crystal display device.

25. A semiconductor device according to claim 19, wherein said semiconductor device is at least one selected from the group consisting of a portable telephone, a video camera, a digital camera, a goggle type display, a personal computer, a DVD player, an electronic book, a mobile computer, and a portable information terminal.

20. A semiconductor device comprising:

a metal substrate;

a base insulating film formed in contact with said metal substrate;

a pixel unit formed over said base insulating film, said pixel unit comprising a thin film transistor having at least a semiconductor layer and a gate electrode with a gate insulating film interposed therebetween;

a first insulating film covering said gate electrode and said semiconductor layer;

a portion of said first insulating film is removed so as to expose a portion of said base insulating film;

a metal wiring formed on said portion of said base insulating film and electrically connected to said semiconductor layer; and

a storage capacitor comprising a portion of said metal substrate, said portion of said base insulating film, and said metal wiring.

26. A semiconductor device comprising:

a metal substrate;

a base insulating film formed in contact with said metal substrate;

a pixel unit formed over said base insulating film, said pixel unit comprising a thin film transistor having at least a semiconductor layer and a gate electrode with a gate insulating film interposed therebetween;

a first insulating film covering said gate electrode and said semiconductor layer;

a portion of said first insulating film is removed so as to expose a portion of said base insulating film;

a metal wiring formed on said portion of said base insulating film and electrically connected to said semiconductor layer;

a pixel electrode electrically connected to said metal wiring; and

a storage capacitor comprising a portion of said metal substrate, said portion of said base insulating film, and said metal wiring.

27. A semiconductor device according to claim 26, wherein a surface of said metal substrate has a maximum roughness of 1 μ

m or less.

28. A semiconductor device according to claim 26, wherein a radius of curvature of a convex part existing in a metal surface of said metal substrate is 1 μ

m or more.

29. A semiconductor device according to claim 26, wherein said metal substrate comprises a stainless steel substrate.

30. A semiconductor device according to claim 26, wherein said semiconductor device is a liquid crystal display device.

31. A semiconductor device according to claim 26, wherein said semiconductor device is at least one selected from the group consisting of a portable telephone, a video camera, a digital camera, a goggle type display, a personal computer, a DVD player, an electronic book, a mobile computer, and a portable information terminal.

32. A semiconductor device comprising:

a metal substrate;

a base insulating film formed in contact with said metal substrate;

a pixel unit formed over said base insulating film, said pixel unit comprising a thin film transistor having at least a semiconductor layer and a gate electrode with a gate insulating film interposed therebetween;

a first insulating film covering said gate electrode and said semiconductor layer;

a portion of said first insulating film is removed so as to expose a portion of said base insulating film;

a metal wiring formed on said portion of said base insulating film and electrically connected to said semiconductor layer;

a second insulating film formed on said metal wiring;

a pixel electrode formed on said second insulating film and electrically connected to said metal wiring; and

a storage capacitor comprising a portion of said metal substrate, said portion of said base insulating film, and said metal wiring.

33. A semiconductor device according to claim 32, wherein a surface of said metal substrate has a maximum roughness of 1 μ

m or less.

34. A semiconductor device according to claim 32, wherein a radius of curvature of a convex part existing in a metal surface of said metal substrate is 1 μ

m or more.

35. A semiconductor device according to claim 32, wherein said metal substrate comprises a stainless steel substrate.

36. A semiconductor device according to claim 32, wherein said semiconductor device is a liquid crystal display device.

37. A semiconductor device according to claim 32, wherein said semiconductor device is at least one selected from the group consisting of a portable telephone, a video camera, a digital camera, a goggle type display, a personal computer, a DVD player, an electronic book, a mobile computer, and a portable information terminal.

38. A semiconductor device according to claim 32, wherein said second insulating film comprises one selected from the group consisting of a polyimide film, an acrylic resin, a polyamide film, and a BCB (benzocyclobutene) film.